Stochastic process algebras have been introduced in order to enable compositional performance analysis. The size of the state space is a limiting factor, especially if the system consists of many cooperating components. To fight state space explosion, various proposals for compositional aggregation have been made. They rely on minimisation with respect to a congruence relation. This paper addre...

PEPA Queues is a formalism that augments queueing networks with customers that have behavioural characteristics, as defined by PEPA components. PEPA Queues suffer from the traditional state-space explosion that affects both closed queueing networks and PEPA models. We discuss a possible solution to this with a continuous state-space approximation that allows us to derive an underlying mathemati...

State space explosion causes most relevant behavioral questions for component-based systems to be PSPACE-hard. Here, we exploit the structure of component-based systems to obtain a first approximation of the reachable global state space. In order to improve this approximation we introduce a new technique we call cross-checking. The resulting approximation can be used to study global properties ...

Approaches to the state space explosion problem in Markovian modelling of concurrent systems are discussed. The emphasis is on structured model description techniques and model simpliication. In particular, it is shown that the exploitation of model symmetries has a potential to drastically reduce the size of the state space. The common features of diierent techniques described in the literatur...

Classical CTL temporal logics are built over systems with interleaving model concurrency. Many attempts are made to fight a state space explosion problem (for instance, compositional model checking). There are some methods of reduction of a state space based on independence of actions. However, in CSM model, which is based on coincidences rather than on interleaving, independence of actions can...

The main analysis techniques for critical systems use state space exploration. However, one is often quickly limited by the so-called state space explosion problem, even if the systems models are relatively small. Several methods have been proposed to tackle this problem in order to get a manageable state space. One of these takes advantage of the modular structure of the model in order to buil...

The use of distributed or parallel processing gained interest in the recent years to fight the state space explosion problem. Many industrial systems are described with large models, and the state space being even larger, it does not fit completely into the memory of a single computer. To avoid the high space requirement, several reduction techniques have been proposed: modular verification, pa...

The use of distributed or parallel processing gained interest in the recent years to fight the state space explosion problem. Many industrial systems are described with large models, and the state space being even larger, it does not fit completely into the memory of a single computer. To avoid the high space requirement, several reduction techniques have been proposed: modular verification, pa...

Planning with actions concurrency under resources and time uncertainty has been recognized as a challenging and interesting problem. Most current approaches rely on a discrete model to represent resources and time, which contributes to the combinatorial explosion of the search space when dealing with both actions concurrency and resources and time uncertainty. A recent alternative approach uses...

Model checking is an effective technique for uncovering subtle errors in concurrent systems. Unfortunately, the state space explosion is the main bottleneck in model checking tools. Here we propose a state space reduction technique for model checking concurrent programs written in C. The reduction technique consists in an analysis phase, which defines an approximate agglomeration predicate. Thi...